Wu, L C; Nangia, V; Bui, K; Hammoor, B; Kurt, M; Hernandez, F; Kuo, C; Camarillo, D B
In Vivo Evaluation of Wearable Head Impact Sensors Journal Article
In: Annals of Biomedical Engineering, vol. 44, no. 4, pp. 1234–1245, 2016.
Abstract | BibTeX | Tags: *Head Movements/ph [Physiology], *Models, *Soccer/ph [Physiology], *Telemetry/is [Instrumentation], adult, Biological, Biomechanical Phenomena, Craniocerebral Trauma, Humans, Male, MOUTH protectors, Skin, Soccer/in [Injuries], VIDEO recording
@article{Wu2016,
title = {In Vivo Evaluation of Wearable Head Impact Sensors},
author = {Wu, L C and Nangia, V and Bui, K and Hammoor, B and Kurt, M and Hernandez, F and Kuo, C and Camarillo, D B},
year = {2016},
date = {2016-01-01},
journal = {Annals of Biomedical Engineering},
volume = {44},
number = {4},
pages = {1234--1245},
abstract = {Inertial sensors are commonly used to measure human head motion. Some sensors have been tested with dummy or cadaver experiments with mixed results, and methods to evaluate sensors in vivo are lacking. Here we present an in vivo method using high speed video to test teeth-mounted (mouthguard), soft tissue-mounted (skin patch), and headgear-mounted (skull cap) sensors during 6-13 g sagittal soccer head impacts. Sensor coupling to the skull was quantified by displacement from an ear-canal reference. Mouthguard displacements were within video measurement error (\<1 mm), while the skin patch and skull cap displaced up to 4 and 13 mm from the ear-canal reference, respectively. We used the mouthguard, which had the least displacement from skull, as the reference to assess 6-degree-of-freedom skin patch and skull cap measurements. Linear and rotational acceleration magnitudes were over-predicted by both the skin patch (with 120% NRMS error for a(mag), 290% for alpha(mag)) and the skull cap (320% NRMS error for a(mag), 500% for alpha(mag)). Such over-predictions were largely due to out-of-plane motion. To model sensor error, we found that in-plane skin patch linear acceleration in the anterior-posterior direction could be modeled by an underdamped viscoelastic system. In summary, the mouthguard showed tighter skull coupling than the other sensor mounting approaches. Furthermore, the in vivo methods presented are valuable for investigating skull acceleration sensor technologies.},
keywords = {*Head Movements/ph [Physiology], *Models, *Soccer/ph [Physiology], *Telemetry/is [Instrumentation], adult, Biological, Biomechanical Phenomena, Craniocerebral Trauma, Humans, Male, MOUTH protectors, Skin, Soccer/in [Injuries], VIDEO recording},
pubstate = {published},
tppubtype = {article}
}
McLeod, P; Reed, N; Gilson, S; Glennerster, A
How soccer players head the ball: a test of Optic Acceleration Cancellation theory with virtual reality Journal Article
In: Vision Research, vol. 48, no. 13, pp. 1479–1487, 2008.
Abstract | BibTeX | Tags: *Head Movements/ph [Physiology], *Motion Perception/ph [Physiology], *Soccer/ph [Physiology], Acceleration, adult, Humans, Male, psychomotor performance, Reaction Time/ph [Physiology], User-Computer Interface
@article{McLeod2008,
title = {How soccer players head the ball: a test of Optic Acceleration Cancellation theory with virtual reality},
author = {McLeod, P and Reed, N and Gilson, S and Glennerster, A},
year = {2008},
date = {2008-01-01},
journal = {Vision Research},
volume = {48},
number = {13},
pages = {1479--1487},
abstract = {We measured the movements of soccer players heading a football in a fully immersive virtual reality environment. In mid-flight the ball's trajectory was altered from its normal quasi-parabolic path to a linear one, producing a jump in the rate of change of the angle of elevation of gaze (alpha) from player to ball. One reaction time later the players adjusted their speed so that the rate of change of alpha increased when it had been reduced and reduced it when it had been increased. Since the result of the player's movement was to regain a value of the rate of change close to that before the disturbance, the data suggest that the players have an expectation of, and memory for, the pattern that the rate of change of alpha will follow during the flight. The results support the general claim that players intercepting balls use servo control strategies and are consistent with the particular claim of Optic Acceleration Cancellation theory that the servo strategy is to allow alpha to increase at a steadily decreasing rate.},
keywords = {*Head Movements/ph [Physiology], *Motion Perception/ph [Physiology], *Soccer/ph [Physiology], Acceleration, adult, Humans, Male, psychomotor performance, Reaction Time/ph [Physiology], User-Computer Interface},
pubstate = {published},
tppubtype = {article}
}
Wu, L C; Nangia, V; Bui, K; Hammoor, B; Kurt, M; Hernandez, F; Kuo, C; Camarillo, D B
In Vivo Evaluation of Wearable Head Impact Sensors Journal Article
In: Annals of Biomedical Engineering, vol. 44, no. 4, pp. 1234–1245, 2016.
@article{Wu2016,
title = {In Vivo Evaluation of Wearable Head Impact Sensors},
author = {Wu, L C and Nangia, V and Bui, K and Hammoor, B and Kurt, M and Hernandez, F and Kuo, C and Camarillo, D B},
year = {2016},
date = {2016-01-01},
journal = {Annals of Biomedical Engineering},
volume = {44},
number = {4},
pages = {1234--1245},
abstract = {Inertial sensors are commonly used to measure human head motion. Some sensors have been tested with dummy or cadaver experiments with mixed results, and methods to evaluate sensors in vivo are lacking. Here we present an in vivo method using high speed video to test teeth-mounted (mouthguard), soft tissue-mounted (skin patch), and headgear-mounted (skull cap) sensors during 6-13 g sagittal soccer head impacts. Sensor coupling to the skull was quantified by displacement from an ear-canal reference. Mouthguard displacements were within video measurement error (\<1 mm), while the skin patch and skull cap displaced up to 4 and 13 mm from the ear-canal reference, respectively. We used the mouthguard, which had the least displacement from skull, as the reference to assess 6-degree-of-freedom skin patch and skull cap measurements. Linear and rotational acceleration magnitudes were over-predicted by both the skin patch (with 120% NRMS error for a(mag), 290% for alpha(mag)) and the skull cap (320% NRMS error for a(mag), 500% for alpha(mag)). Such over-predictions were largely due to out-of-plane motion. To model sensor error, we found that in-plane skin patch linear acceleration in the anterior-posterior direction could be modeled by an underdamped viscoelastic system. In summary, the mouthguard showed tighter skull coupling than the other sensor mounting approaches. Furthermore, the in vivo methods presented are valuable for investigating skull acceleration sensor technologies.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
McLeod, P; Reed, N; Gilson, S; Glennerster, A
How soccer players head the ball: a test of Optic Acceleration Cancellation theory with virtual reality Journal Article
In: Vision Research, vol. 48, no. 13, pp. 1479–1487, 2008.
@article{McLeod2008,
title = {How soccer players head the ball: a test of Optic Acceleration Cancellation theory with virtual reality},
author = {McLeod, P and Reed, N and Gilson, S and Glennerster, A},
year = {2008},
date = {2008-01-01},
journal = {Vision Research},
volume = {48},
number = {13},
pages = {1479--1487},
abstract = {We measured the movements of soccer players heading a football in a fully immersive virtual reality environment. In mid-flight the ball's trajectory was altered from its normal quasi-parabolic path to a linear one, producing a jump in the rate of change of the angle of elevation of gaze (alpha) from player to ball. One reaction time later the players adjusted their speed so that the rate of change of alpha increased when it had been reduced and reduced it when it had been increased. Since the result of the player's movement was to regain a value of the rate of change close to that before the disturbance, the data suggest that the players have an expectation of, and memory for, the pattern that the rate of change of alpha will follow during the flight. The results support the general claim that players intercepting balls use servo control strategies and are consistent with the particular claim of Optic Acceleration Cancellation theory that the servo strategy is to allow alpha to increase at a steadily decreasing rate.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Wu, L C; Nangia, V; Bui, K; Hammoor, B; Kurt, M; Hernandez, F; Kuo, C; Camarillo, D B
In Vivo Evaluation of Wearable Head Impact Sensors Journal Article
In: Annals of Biomedical Engineering, vol. 44, no. 4, pp. 1234–1245, 2016.
Abstract | BibTeX | Tags: *Head Movements/ph [Physiology], *Models, *Soccer/ph [Physiology], *Telemetry/is [Instrumentation], adult, Biological, Biomechanical Phenomena, Craniocerebral Trauma, Humans, Male, MOUTH protectors, Skin, Soccer/in [Injuries], VIDEO recording
@article{Wu2016,
title = {In Vivo Evaluation of Wearable Head Impact Sensors},
author = {Wu, L C and Nangia, V and Bui, K and Hammoor, B and Kurt, M and Hernandez, F and Kuo, C and Camarillo, D B},
year = {2016},
date = {2016-01-01},
journal = {Annals of Biomedical Engineering},
volume = {44},
number = {4},
pages = {1234--1245},
abstract = {Inertial sensors are commonly used to measure human head motion. Some sensors have been tested with dummy or cadaver experiments with mixed results, and methods to evaluate sensors in vivo are lacking. Here we present an in vivo method using high speed video to test teeth-mounted (mouthguard), soft tissue-mounted (skin patch), and headgear-mounted (skull cap) sensors during 6-13 g sagittal soccer head impacts. Sensor coupling to the skull was quantified by displacement from an ear-canal reference. Mouthguard displacements were within video measurement error (\<1 mm), while the skin patch and skull cap displaced up to 4 and 13 mm from the ear-canal reference, respectively. We used the mouthguard, which had the least displacement from skull, as the reference to assess 6-degree-of-freedom skin patch and skull cap measurements. Linear and rotational acceleration magnitudes were over-predicted by both the skin patch (with 120% NRMS error for a(mag), 290% for alpha(mag)) and the skull cap (320% NRMS error for a(mag), 500% for alpha(mag)). Such over-predictions were largely due to out-of-plane motion. To model sensor error, we found that in-plane skin patch linear acceleration in the anterior-posterior direction could be modeled by an underdamped viscoelastic system. In summary, the mouthguard showed tighter skull coupling than the other sensor mounting approaches. Furthermore, the in vivo methods presented are valuable for investigating skull acceleration sensor technologies.},
keywords = {*Head Movements/ph [Physiology], *Models, *Soccer/ph [Physiology], *Telemetry/is [Instrumentation], adult, Biological, Biomechanical Phenomena, Craniocerebral Trauma, Humans, Male, MOUTH protectors, Skin, Soccer/in [Injuries], VIDEO recording},
pubstate = {published},
tppubtype = {article}
}
McLeod, P; Reed, N; Gilson, S; Glennerster, A
How soccer players head the ball: a test of Optic Acceleration Cancellation theory with virtual reality Journal Article
In: Vision Research, vol. 48, no. 13, pp. 1479–1487, 2008.
Abstract | BibTeX | Tags: *Head Movements/ph [Physiology], *Motion Perception/ph [Physiology], *Soccer/ph [Physiology], Acceleration, adult, Humans, Male, psychomotor performance, Reaction Time/ph [Physiology], User-Computer Interface
@article{McLeod2008,
title = {How soccer players head the ball: a test of Optic Acceleration Cancellation theory with virtual reality},
author = {McLeod, P and Reed, N and Gilson, S and Glennerster, A},
year = {2008},
date = {2008-01-01},
journal = {Vision Research},
volume = {48},
number = {13},
pages = {1479--1487},
abstract = {We measured the movements of soccer players heading a football in a fully immersive virtual reality environment. In mid-flight the ball's trajectory was altered from its normal quasi-parabolic path to a linear one, producing a jump in the rate of change of the angle of elevation of gaze (alpha) from player to ball. One reaction time later the players adjusted their speed so that the rate of change of alpha increased when it had been reduced and reduced it when it had been increased. Since the result of the player's movement was to regain a value of the rate of change close to that before the disturbance, the data suggest that the players have an expectation of, and memory for, the pattern that the rate of change of alpha will follow during the flight. The results support the general claim that players intercepting balls use servo control strategies and are consistent with the particular claim of Optic Acceleration Cancellation theory that the servo strategy is to allow alpha to increase at a steadily decreasing rate.},
keywords = {*Head Movements/ph [Physiology], *Motion Perception/ph [Physiology], *Soccer/ph [Physiology], Acceleration, adult, Humans, Male, psychomotor performance, Reaction Time/ph [Physiology], User-Computer Interface},
pubstate = {published},
tppubtype = {article}
}